Regular or Premium Gasoline Required?
11-14-16, 04:20 PM
#61
Driver School Candidate
This site might be interesting if you are wondering about brands and additives, It is sponsored by BMW, General Motors, Fiat Chrysler, Honda, Toyota, Volkswagen, Mercedes-Benz and Audi. It sets a minimum standard and shows the brands that meet this standard.
www.toptiergas.com
http://www.toptiergas.com/
www.toptiergas.com
http://www.toptiergas.com/
11-15-16, 05:05 AM
#64
Pole Position
Another gas thread.
It is like religion, believe what you want.
My religion on gas is to use a good brand name regular grade in both RX and LX and have never had a problem. In my LX you lose about 2-3 HP as Toyota has the same motor in the Land Cruiser which the recommend regular with 2-3 less HP. When they delivered my LX they filled it up with regular as do most Lexus dealers.
If premium make you feel better, go for it.
It is like religion, believe what you want.
My religion on gas is to use a good brand name regular grade in both RX and LX and have never had a problem. In my LX you lose about 2-3 HP as Toyota has the same motor in the Land Cruiser which the recommend regular with 2-3 less HP. When they delivered my LX they filled it up with regular as do most Lexus dealers.
If premium make you feel better, go for it.
03-04-17, 04:57 PM
#66
Advanced
Thread Starter
No. And higher octanes should give you poorer gas mileage since octane enhancers (such as ethanol) have less energy per volume than the gasoline that they replace in order to increase the octane rating.
03-04-17, 07:17 PM
#67
Most Regular Gas in Albuquerque, NM is 86 Octane, owner's manual sez to use 87 or higher, so I use Premium mostly as Regular Gas does not meet the Owner's Manual requirement... Some gas stations in Oklahoma still sell "Real Gas" without alcohol at a price increase. NM does not have that.
03-05-17, 11:01 AM
#68
I have some knowledge on this subject. you can run either or, of course 91 is better for performance.
Heres why, your computer is monitored by knock sensors to prevent detonation Thats the killer to your motor.
So when you do not have enough octane in the fuel the knock sensers will detect this and adjust your timing.
Timing, fuel/air are the key to HP. Decrease timing, lower HP. That said you will not do any damage to your engine
by running lower octane but you will definitely give up some performance. Keep in mind thar your computer will
only adjust so far so running 91oct gives you the benefit of peformance and gives you a safety buffer in case the
fuel octane is not quite what it says. Hope this helps.
Heres why, your computer is monitored by knock sensors to prevent detonation Thats the killer to your motor.
So when you do not have enough octane in the fuel the knock sensers will detect this and adjust your timing.
Timing, fuel/air are the key to HP. Decrease timing, lower HP. That said you will not do any damage to your engine
by running lower octane but you will definitely give up some performance. Keep in mind thar your computer will
only adjust so far so running 91oct gives you the benefit of peformance and gives you a safety buffer in case the
fuel octane is not quite what it says. Hope this helps.
03-06-17, 07:36 AM
#69
Any input on the effect of 85 octane in high altitude areas like Colorado? Regular octane here is 85, which I believe is because of the way altitude affects detonation? I have heard that it operates the same as 87 at sea level but I would like to know from someone with more knowledge than myself.
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Toniann966 (03-13-17)
03-07-17, 09:25 AM
#72
Driver School Candidate
03-07-17, 10:31 AM
#74
".........For temperature, it seems that approximately every 7C +/- results in a change of +/- 1 ON. Which means if your car requires 91 in the summer, in the winter it would only require 87.
For altitude, it seems to be about a reduction of 3-4 ON per increase of ~1000m (or 10 kPa).
Spark advance/retard of 1 degree (360 degrees is a full engine revolution) results in a change of 1 ON.
So essentially, if you live at 3000 ft, or in cold climates, you could run a premium designed engine on regular, and the knock sensor would probably not even get triggered (assumed the engine was designed to run at sea level during temperate climates)....."
For altitude, it seems to be about a reduction of 3-4 ON per increase of ~1000m (or 10 kPa).
Spark advance/retard of 1 degree (360 degrees is a full engine revolution) results in a change of 1 ON.
So essentially, if you live at 3000 ft, or in cold climates, you could run a premium designed engine on regular, and the knock sensor would probably not even get triggered (assumed the engine was designed to run at sea level during temperate climates)....."
Last edited by ericsan13; 03-07-17 at 03:23 PM. Reason: Bad maths
04-12-17, 06:53 AM
#75
I wondered about the line in the owner's manual that said 87 octane or higher was required. So over the last month or so I did 3 weeks of regular fill ups and 3 weeks of premium fill ups. I had 2 regular fill ups and hand calculated 19.4mpg. [Tank was run down to 15 mile range before filling with premium.] I did 2 premium fill ups and hand calculated 22.1mpg. City to highway ratio was hand calculated based on average speed between fill ups to be between 55-60% city.
I also have a wireless OBD II reader that calculates HP and torque. Max HP on regular was 297hp at 6147rpm and 279ft/lb at 4208 rpm. Max HP on premium was 307 at 5742rpm and 297ft/lb at 3630 rpm. Numbers were generated in sport mode by flooring the car while merging onto the highway. Acceleration from roughly from 30mph to 80mph. The car determined the shifts but it appeared to be near redline (~6450rpm).
This wasn't a well controlled experiment but interesting none the less.
I also have a wireless OBD II reader that calculates HP and torque. Max HP on regular was 297hp at 6147rpm and 279ft/lb at 4208 rpm. Max HP on premium was 307 at 5742rpm and 297ft/lb at 3630 rpm. Numbers were generated in sport mode by flooring the car while merging onto the highway. Acceleration from roughly from 30mph to 80mph. The car determined the shifts but it appeared to be near redline (~6450rpm).
This wasn't a well controlled experiment but interesting none the less.